This article draws from the insights offered by discourse analysis and the study of gesture to examine imagination as a product of, and resource for, social action. Using data collected during ethnographic fieldwork at an architecture firm, the article explores how imagining can emerge from a group of interactants who use many semiotic media, including talk, gestures, and drawings, to imagine something together. Following the groundwork laid by Benedict Spinoza, this perspective moves the "object" of imagination out of the brain, away from mental imagery and into the space in which shared activities take place. Such a move has implications for rethinking imagination in terms of communicative interaction and social activity. (Contains 3 footnotes.)